In Cortana Microsoft has good grounds for claiming it has built the best virtual assistant in the market today. However if you're outside of the US it continues to be a frustrating and compromise ridden experience to even get access to use it.
Cortana is not a new product and the glacial global rollout of its features and platform support is a very old Microsoft thing and not what we should be expecting of a company which seems to have left most of its bad old ways behind.
Right now the only way to get Cortana working on any device outside of the US (and in the UK in some cases) involves some form of compromise. Either changing your region, language or speech settings to US English, losing access to your native Windows Store in the process.
Now I understand that localising Cortana for different languages might prove to be a challenge which requires some effort on Microsoft's part but I see no reason why various English-speaking countries shouldn't be able to leverage the virtual assistant now. In their local language, store, region, etc.
If necessary flag it as a beta and warn users when they enable Cortana in their local English variation that some results may not be ideal. But at least let them try.
Because it doesn't matter how many new features, skills and integrations Microsoft brings to the table, if users outside of the US can't use Cortana it will fail.